Steam iron



March 28, 1961 KlsTNER ET AL 2,976,627

STEAM IRON Filed Nov. 4, 1958 H llu FIG. 3

INVENTORS MERRILL M. KISTNER EDWARD G F J1MML MId-N MM+ a TESMER ATTORNEYS Unie STEAM IRON Filed Nov. 4, 1958, Ser- No. 771,819

Claims. (Cl. 38-77) This invention relates to steam irons and more particularly to control means for regulating the flow of water from the reservoir to the steam generating chamber of a steam iron of the flash type, and also controlling the setting of the thermostat of the iron.

Heretofore steam irons have been made of two types, the flash type and the boiler type. In flash type irons, as disclosed in Kistner prior Patents No. 2,313,382 granted March 9, 1943, and No. 2,384,839 granted September 18, 1945, a quantity of water is contained in a reservoir mounted over the sole-plate and the water is delivered through a valve-controlled outlet to a steam generating chamber in the sole plate. The steam may flow from the steam generating chamber through channels in the sole-plate to outlet or discharge openings in the soleplate to properly condition the steam, as disclosed and claimed in Patent No. 2,384,839.

In commercial steam irons at present available, it is the usual practice to provide valve-controlled means for the delivery of Water to the steam generating chamber that is incapable of regulation, i.e the valve has only an on position and an oil position. To obtain the full advantages of an iron of this type, the water control should be capable of regulation. When pressing heavier fabrics requiring higher temperatures, larger quantities of steam should be supplied.

In addition, as the temperature of the sole-plate is increased, the amount of steam generated should be proportionately increased to assure production of a uniform type of steam at all temperatures. For best operation, a steam iron should produce steam that is not too wet, that is, does not contain any appreciable quantity of water droplets in liquid form. Such steam causes spotting of various fabrics. On the other hand, the steam should not be superheated to an appreciable amount. If it is, no condensation will take place in the fabric and the fabric will not be conditioned in the pressing operation in the manner that a properly constructed and properly used steam iron is capable of conditioning fabric.

It will be apparent that a certain portion of the heat supplied by the heating element of an iron is used for heating the sole-plate and a certain proportion is used to vaporize the water supplied to the steam generating chamber and condition the steam before it is delivered to the discharge ports. This proportion is roughtly the same at any setting of the thermostat. It will thus be apparent that in an iron having only one rate of water delivery to the steam generating chamber, the type of steam delivered will vary with different thermostat settings. If a properly conditioned steam is delivered with a low thermostat setting, a higher setting requiring a greater heat input to maintain the sole-plate at the higher temperature, will result in superheating the steam to an extent that the iron does not properly condition the fabric, because insufllcient steam is condensed in the fabric. Likewise, if the steam delivered is in proper condition with a high setting, a lower setting will result in the delivery of 2,976,627 Patented Mar. 28, 1961 fabrics.

In a copending application of Merrill M. Kistner, Senal No. 617,777 filed October 23, 1956, now Patent No.

2,903,804 granted September 15, 1959, he has disclosed a flash type iron in which the water delivery of the irontis correlated to the temperature setting of the thermostat, and in which a single control member regulates the setting of the valve and the thermostat. The present invention is directed to improved means to accomplish the valve regulation and thermostat setting.

In the present invention we provide control means for the thermostat and valve operated by a single member mounted in the front leg of the handle of the iron. Such member is preferably in the form of a disc, mounted concentrically of the valve stem and having means such as a cam to raise the valve stem against the force of the spring that normally biases the valve to a closed posi tion. The cam may, through suitable connecting means, vary the opening of the valve depending upon the position to which it is adjusted. Suitable means, illustrated as meshing gears and a shaft, may also transmit movement of the disc to the thermostat control rod to permit adjustment of the temperature of the iron. The disc may also be provided with a portion in alignment with the water cam which will permit the valve to remain closed throughout an appreciable range of adjustment of the disc and thermostat control rod thus permitting adjustments of the temperature setting when the iron is used as a dry iron.

In the accompanying drawing, we have-shown one embodiment of the invention. In this showing:

Fig. 1 is a side elevation of an iron, portions being shown in vertical section to illustrate the invention;

Fig. 2 is a horizontal sectional view on line 22 of Fig. 1; and

Fig. 3 is an enlarged view of a portion of the mecha nism shown in Fig. l.

Referring to the drawing, the iron is generally the conventional flash type domestic iron, including a sole-plate 2, over which is mounted a reservoir 4, enclosed by a shell 6 on which is mounted a handle 8. The reservoir is provided with a member 10 forming a valve seat 12 which cooperates with valve 14 to control delivery of water. Valve 14 is formed on the lower end of valve stem 16 which extends upwardly through the handle as shown. Water is delivered from the reservoir to a steam generating chamber 18 in the soleplate. The sole-plate may be of the construction shown in Kistner Patent 2,384,839, having discharge ports (not shown) connected by channels (not shown) to the steam generating chamber. A heating element (not shown), generally in the form of a U and following the contour of the sole-plate, is embedded in the sole-plate. The terminals of the heating element are connected to electric cord terminals (not shown) in the rear leg of handle 8. A thermostat 20, generally arranged in a recess in the rear portion of the sole-plate, is connected between one of the cord terminals and one of the terminals of the heating element. The sole-plate, reservoir, shell and handle are secured to each other by conventional means. Part of the fastening means consists of a stud 22 which has a threaded lower end 24 received in a threaded opening in the soleplate and a threaded upper end which receives a nut 26 engaging the top of the shell. The parts heretofore described are of usual construction, and form no part of the present invention except in combination with the parts to be described.

The front leg of the handle is provided with a bore 28 through which stem 16 extends. A spring 30 surrounds the valve stem between the upper end of the bore and a stop pin 32 and biases the valve toward a closed and valve.

position. The lower end 34 of the front leg is shaped to pass through an opening in the shell and into an opening in the top of the reservoir. Bore 28 communicates with an opening 36 in the front of the leg which forms a filling opening.

Above the bore 28, the handle is recessed to receive a control disc 38. This disc is concentric with, and surrounds the valve stem, being free to rotate on the valve stem. As shown, it is of such size that it projects slightly beyond the handle in front to permit it to be rotated by hand, to set the thermostat, or the thermostat It is provided with suitable indicia 40 to indicate thermostat settings corresponding to the positions of the disc.

The disc 38 is provided with a series of earns 42 by means of which the valve stem may be raised, against the compression of spring 30, to open the valve to one of several positions. As shown, a sleeve 44 surrounds the valve stem and carries a radial arm 46 which extends through a slot 48 in the portion 50 of the handle surrounding the sleeve. The sleeve is thus capable of movement axially of the valve stem, but is prevented from moving circumferentially by the arrangement of arm 46 in slot 48. Sleeve 44 carries a cam or operating member 52 on its upper face. A knob 54 is secured to the upper end of the valve stem, and a member 56 is secured to the valve stem below the knob. The member 56 is provided with a cam surface on its lower face providing cam portions 58 and 60. The relationship of cam portions 58 and 60 to cams 42 on disc 38 is such that when the knob is turned to bring operating member 2 into alignment with the deeper cam 58, arm 46 may ride over the highest portion of cam 42 without raising member 44 high enough to lift the member 56, and thus raise the valve stem to open the valve. Therefore, with the parts in this position, the iron may function as a dry iron and disc 33 may be adjusted to obtain any desired thermostat setting, as hereinafter described.

The dimensions of the various parts of the valve control are such that when the knob 54 is turned to vertically align operating member 52 and cam portion 60, valve 14 will remain closed as long as arm 46 is in contact 'with the low portion of cam area 42. As the disc is turned to raise the sole-plate temperature, for instance, from 300 F. to 400 F. as indicated in Fig. 2, arm 46 engages progressively higher portions of cam 42 and thus opens valve 14 to increase the flow of water to the soleplate as the ironing temperature is raised.

As stated, disc 38 also controls the setting of thermostat 20 to regulate the operating temperature of the iron. 0

are provided for the valve and thermostat, this rod is connected to a control member arranged on top of the shell, beneath the gripping portion of the handle. in our improved iron a coupling 64 on the upper end of rod 62 carries a gear or pinion 66. The upper end of coupling 64 is received in a plate 68 carried by stud 22, and arranged beneath the shell. An idlergear 70, mounted on stud 22 above a washer 72 meshes with pinion 66. A shaft 74 extends through an opening in the handle and carries a pinion 76 on its lower end, beneath the shell and in mesh with gear 70. The upper end of shaft 74 is received in a slot 78 in the lower face of disc 38 and therefore does not interfere with the rotation of disc 33. It carries a pinion 80 adjacent its upper end which meshes with a centrally arranged gear 82 on the lower face of disc 38. Thus the rotation of disc 38, through gears 82 and 80, shaft 74, pinions 76, 70 and 66 and coupling 6 actuates control rod 62 to set the thermostat.

It will thus be seen that when knob 54 is set to align operating member 52 and cam portion 60 so that any 4 vertical movement of member 50 is transmitted to the valve stem, rotation of disc 38 simultaneously sets the thermostat and adjusts the opening of valve 14. By properly designing and dimensioning the parts, the quantity of water can be proportioned to the heat input for varoius thermostat settings to produce steam of substantially the same characteristics for any temperature setting. When the iron is to be used as a dry iron, knob 54 is turned to vertically align operating member 52 and cam portion 53. Sleeve 50 can then be raised to its uppermost position before member 52 will reach the bottom of cam portion 58 and raise the valve stem. The valve is thus retained closed by spring 30 for any setting of disc 38 and thermostat 2t], permitting use of the iron as a dry iron.

We claim:

1. In an electric steam iron comprising a sole-plate having a steam generating chamber, steam delivery channels in the sole-plate and outlet openings in its lower face, a water reservoir over the sole-plate, a handle over the reservoir, said handle comprising front and rear legs and a gripping portion, the sole-plate, reservoir and handle being operatively connected to each other to form a unitary structure, a valve controlling delivery of water from the reservoir to the steam generating chamber, a valve stem connected to the valve, a thermostat to control the temperature of the-sole-plate, and a thermostat control rod associated with the thermostat, that improvement which comprises a control disc mounted in the front leg of the handle, a gear carried by the disc, means operatively connecting the thermostat control rod to the gear to regulate the thermostat, a series of cams arranged on the disc, a valve control member surrounding the valve stem and having a portion thereof riding on said cams to raise said member when the disc is rotated, said member being operatively keyed to the valve stem so that the stem is raised and the valve is opened when said member is raised by the cams.

2. Apparatus in accordance with claim 1 wherein the series of cams are concentrically arranged on the upper surface of the disc and the valve control member comprises a sleeve surrounding the valve stem and having an arm which rides on said cams.

3. Apparatus in accordance with claim 2 wherein a connecting member is secured to the valve stem and said connecting member is provided with cam portions on its lower face to be engaged by said sleeve, and wherein one of said cam portions is dimensioned to permit movement of said sleeve on said valve stem without transmitting movement to the stem.

4. Apparatus in accordance with claim 1 wherein a shaft extends downwardly from said disc in the front leg of the handle through the top of the shell, a pinion on the top of said shaft meshes with the gear on the disc to rotate the shaft, and means are provided connecting the lower portion of said shaft to the thermostat control rod.

5. Valve operating means for a steam iron comprising a valve stem biased toward a closed position, an operating member mounted on said stem to permit vertical movement of said member with respect to the stem, control means to raise said member, and a connecting member secured to the valve stem above said operating member, the lower surface of said connecting member being provided with a plurality of cam portions engaged by said operating member, one of said cam portions being dimensioned to permit movement of said operating memher without moving said valve stem.

References Cited in the file of this patent lepson Feb. 3, 19-59 

